Petroski on Engineering: Envelopes of Experience

I can't remember exactly when my correspondence with Chuck Siple began, but I'm sure it had its origins in his writing to me about something in one of my books on design. And I expect that he was supplementing what I wrote, was providing an excellent further example of good or poor design, or was simply reporting on a discovery or observation that he made while reading or shopping. In any case, that is what I have come to expect from a Chuck Siple missive.

Chuck's hand-written letters are of the old school -- cursive and discursive. The salutations have calligraphic flourishes, and the closings have even grander and more expansive flourishes. In between, his small, tight handwriting for a long time was executed with a turquoise-colored ink in his fountain pen, though his latest seem to be in black ballpoint, but that has not diminished their allure. There are often postscripts and post-postscripts, and enclosures of clippings. But what makes Chuck's letters more than mere epistles is his frequent interruption of the prose with drawings -- of a recently encountered elegant, curious, or faulty design.

The drawings that Chuck makes are masterful, with perfect perspective and fine detail. When he is describing a process, he will provide a series of drawings, showing the step-by-step progression of the action. In a recent letter, for example, he reported with obvious excitement about his coming across at the supermarket of a self-threading sewing needle. He wrote that he was going to buy a pack of 10 and send me one, but the price was too dear for a retiree. Instead, he provided three drawings showing enlarged views of the needle's eye end showing the steps by which it was threaded.

Chuck has a clear talent for technical drawing. He is a retired patent draftsman, and like a lot of retirees he has continued to practice his craft in a modified form. Some years ago, when my son and I were applying for a patent, Chuck was kind enough to execute from our sketches the final drawings in conformity with patent office requirements, with which he was intimately familiar. In appreciation of his help, I sent him a pear-wood 30-60-90-degree drafting triangle that I had come across in an antique store. It was a thing of beauty, I thought, and I believed that he would not only see it as that but also might put it to use.

After he read my book on delivering newspapers, in which I tried to describe in words alone how we paperboys in the 1950s folded the papers so that we could toss (or "flip") them from our bicycles onto subscribers' stoops and porches, Chuck sent me a series of illustrations showing the steps he used in folding the papers he delivered as a boy. I reproduced (with his permission) Chuck's fine drawings in a subsequent article on the variety of folding schemes that had been used by paperboys at different times in different parts of the country, thus demonstrating how a single design problem can have many different solutions.

I started as a designer and then an engineer on the drafting board. I wasn't a good draftsman, so I embraced CAD with a passion. Even with a template I could rarely letter well. For me the thing I miss is the art, and it truly is an art, of a sophistacated cutaway drawing. Road & Track magazine had at least two illustrators of superb skill. I loved the details. I have always been a 3D guy, thinking and visuallizing my projects well. However I was always jealous of the skill of being able to draw those cutaways! Our CAD machines and programs will produce a perfect sectional drawing but it is not the same. The summit of the old school cutaways I have seen is the cutaway of the Rolls Royce Crecy piston engine. I don't believe the draftsman even signed it, but he should have it was a thing of beauty. It is appropriate that it was the best cutaway I know of as the Crecy was pretty much the pinnacle of piston engine design circa 1945. The jet engines replace those big aircraft piston engines, but are not as technically interesting, to me at least. The CAD era produces more technically correct drawings, but they will never be as interesting as the hand inked cutaways. Bill J

I was never very good at drafting. I remember taking a class in high school and I always smudged my drawings. I actually don't remember if we had a mechanical drawing class in college. Don't think so since I was a EE major. On my first job, we had a whole area of about 20 draftsman. Like one of the commenters said below, these were all non-degreed guys who probably migrated to the field after WWII or Korea via trade schools. I admire the skill and I enjoyed Henry's column. I usually lament the passing of older technologies -- I'm still a big vacuum tube fan -- but in the case of drawing I don't see that much has been lost by the shift from pencil to CAD.

In high school we had basic and advanced mechanical drawing, and even architectural drawing and rendering.In those days, one worked very hard just to qualify to enter the Illinois Institute of Technology drafting competition.To win any kind of an award would be an honor, indeed!

With the emphasis on using CAD to produce drawings, we are losing the hand-eye-brain interconnection; a way to get the "feel" of an object, and to have one's mind sense the object's shape, construction, and texture.In the same way, learning cursive writing refined that very same hand-eye-brain interconnection, aiding not only clear writing, but clear thinking.

I am not a Luddite who might say down with CAD, texting, or word processing.I understand the utility of, and use these systems, but I do see this as a further erosion of the "humanness" of communication.

I believe that learning to sketch and to write clearly, prepares one's mind to understand the observer's world before trying to improve it.I further believe that learning these skills should remain in the engineering curriculum.

Like everyone else, i have always admired Petroski for his design genius but his language skills in explaining the engineering thoughts are also commendable. As Wittgenstein said that the limits of one's language the limits of the world, it is important to have language skills to express and explain the engineering view. Every time i read Petroski i am motivated by his language skills. I know this comment may not be related to the topic , but still i felt like paying tributes to his writing skills.

At present, I am not sure if board drafting is still being taught in schools which is actually kind of sad. However, I have shown my kids the finer points of drafting. I pulled an old drawing board from a dumpster of a closing company and set up my own drafting station in my work shop. I do full engineering style drawings of any wood project that I work on. I also do my best to introduce my kids to the 1/8" dashes seperated by 1/16" space to mark a hidden line. They look at me like I am crazy, but I still enjoy it.

This waxing sentimental brings back so many memories – Architectural Rendering in High School; 3-point perspective drawing; My first job as a Detailer in a Tool&Die shop in 1978;remembering to always slowly twist the pencil between your thumb & finger to avoid generating a flat (caused inconsistent line widths!) Descriptive Geometry & Spatial Relationships.Each of these things was a specific blend of talents in Art & Technology.Thanks for the memories; so much of this is a lost art that so few ever heard of, let alone could ever appreciate!

Drafting talents like Chuck's are hard to come by today. When I started out as an engineer, the company I worked for had a very talented, non-degreed engineer/draftsman named Franz who drew beautiful oblique views of bridges of all types. The drawings were so good that I've kept some for more than 30 years. His work was actually inspiring because he took what was a science (to the rest of us, at least) and turned it into an art.

Reading this article, I have a clear picture in my mind of what these envelopes must look like. It makes me long for the days when I would go to the store and buy a new box of pretty, crisp stationary. I'm sure "pen pals" still exist, but not by snail mail. "sigh."

Industrial workplaces are governed by OSHA rules, but this isn’t to say that rules are always followed. While injuries happen on production floors for a variety of reasons, of the top 10 OSHA rules that are most often ignored in industrial settings, two directly involve machine design: lockout/tagout procedures (LO/TO) and machine guarding.

Load dump occurs when a discharged battery is disconnected while the alternator is generating current and other loads remain on the alternator circuit. If left alone, the electrical spikes and transients will be transmitted along the power line, leading to malfunctions in individual electronics/sensors or permanent damage to the vehicle’s electronic system. Bottom line: An uncontrolled load dump threatens the overall safety and reliability of the vehicle.

While many larger companies are still reluctant to rely on wireless networks to transmit important information in industrial settings, there is an increasing acceptance rate of the newer, more robust wireless options that are now available.

To those who have not stepped into additive manufacturing, get involved as soon as possible. This is for the benefit of your company. When the new innovations come out, you want to be ready to take advantage of them immediately, and that takes knowledge.

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